


bro

by alchemist17



Category: Voltron: Legendary Defender
Genre: Anal Sex, Frottage, Incest Kink, M/M, Sibling Incest
Language: English
Status: Completed
Published: 2018-08-10
Updated: 2018-10-07
Packaged: 2019-06-25 12:19:06
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 2
Words: 2,543
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/15640632
Author URL: https://archiveofourown.org/users/alchemist17/pseuds/alchemist17
Summary: hatemail for those fans. you know those i mean.in which keith has an incest kink which is poorly hiddenAnd then just some soft pwp incest sheith





	1. Chapter 1

**Author's Note:**

> me: wow i love sheith, there's truly nothing this pairing is missing  
> my nasty brain: incest. we're missing incest

It was just something Keith had always called him, part of his idiolect. It was weird the first couple of times but Keith didn’t think it was a big deal so Shiro didn’t either.

“Fuck bro, that feels good.”

Sometimes, if he’s drifting and Keith addresses him as ‘bro’ to get his attention back… Shiro feels the heat like a solar flare in his stomach. Only because it reminds him of when they’re in bed.

“Bro, harder. Fuck my ass harder.”

But usually he doesn’t. Usually he has absolutely no reaction because that’s just what Keith calls him. He’d probably call any other guy ‘bro’ while they’re fucking.

“I’m gonna come, bro.”

He leans forward over Keith, butts his nose into his cheek to get close.

“Keith?”

“Huh?”

“I want you to come, bro.”

 

After, they lie there with the sweat drying on their skin, Shiro wrapped around his lover like a blanket.

“You’ve never called me that before.”

“Hmm?”

“Bro.”

“Thought you might like it.”

“I did.” Keith pauses, swallow. “Thanks.”

“S’fine. Do you want to talk about it?”

“No.”

“Okay. Night bro.”

“Night bro.”

But Shiro can’t stop thinking about it. How close he felt to Keith, sharing their bodies, their breath, the impossible idea that they might share blood.

 

He’s still thinking about it the next time Keith crawls beneath the covers to wake him up. Shiro’s seized by an image, a thought, of Keith creeping into his room early in the morning before their parents wake. Shiro moans at the thought and Keith shushes him. It burns through him and he can’t help but reach down to push the blanket aside, to see Keith’s precious face as he nurses Shiro’s dick.

“Baby bro…” He sighs, reaching for Keith's arms to pull him up. 

Keith is ghostly pale with horror, unmoving as Shiro holds him close.

“I’m so lucky to have a pretty little brother like you.”

He relaxes a little against Shiro. “Big bro?”

“I’m here.”

Keith blinks as he wells up. “You’re so much better than I deserve.” He gets off of Shiro, hugs his knees.

“Oh no, Keith, what’s wrong? I thought you’d like it.” Shiro grabs his shoulder to ease him back into the crook of his armpit.

“I do. Really. I just, uh.” Keith wipes his eyes. “I know I shouldn’t be into it. And I shouldn’t push it on you, and you don’t have to play along, really.”

“You don’t have to be ashamed of anything, not with me. Let’s talk about it.”

“Alright. Let’s talk about it. Like grown-ups.” He lays his hands on his chest, fiddles as he talks. “I first thought of you as some cool older brother. And then I hit puberty and noticed how hot you are but I never managed to separate ‘brother Shiro’ from ‘Shiro I want to fuck’.”

“Puberty is a strange time. I put a model of the space shuttle up my arse and jacked off. More than once. I broke the little wings by the nose off first.”

“Oh my god. The broken model of the old NASA shuttle they sent me when they cleared your room?”

“That’s it. Always wondered what they did with my stuff.”

“It’s back at the shack.”

“They sent you my stuff?”

“Yeah. We’re listed as each other’s next of kin, remember.”

“Hmm.”

They lay there for several minutes.

“So,” Shiro starts. “you like calling me bro because…”

“It makes me feel close to you.”

Shiro nods. “And you like calling me it in bed because…”

“I find it arousing.”

“So do I.”

“Shiro, really, you don’t have to pretend.”

“I just told you I used to shove a rocket up my ass but you’re doubting I would be into this?”

“But it’s gross.”

“So is sticking my tongue up your arse but you like that.”

Keith sighs. “I do like that.” He rolls over to peer at Shiro. “So, you wanna take it from the top? Me, the adoring, impressionable younger brother desperate for approval, and you, a helpless slave to your own lust.”

“Shit.” Shiro says thickly. “Keep going.”

“You’ve been trying to resist for so long, insisting it’s natural to be so possessive of your little brother. It’s normal to be so  complimentary , to be so tactile. And when I come into your room and crawl beneath the sheets to wake you you just can’t bring yourself to push me away.”

Shiro rolls them over. He rubs himself against Keith, bites at his ear.

“Be gentle, bro. I’ve never done this before.” Keith says, fluttering his eyelashes.

Shiro groans, scrambling for the lube. “I’ll be gentle, baby brother.”

They’re both bright red with arousal and embarrassment as Shiro shoves his fingers in. It’s rougher than he should be for this role but they have time. They’ll try again. But for now Shiro scoops one of Keith’s knees onto his shoulder, bends down to kiss him as he sinks the head in.

“Shiro, brother.” Keith whines, nails scraping over his back as he tries to pull Shiro closer. “Please fuck me.”

Shiro feels like he’s burning. Burying his cock helps but not for long and soon he’s pounding into Keith.

“How does that feel, baby brother? Do you like that?” He grits out against his neck, damp with his breath and sweat. 

“It feels so good, big bro.”

“Do you think you can come like this? On just your brother's cock?”

Keith nods.

“You’re so perfect. I’ve barely touched you.” He says in awe. “I’m gonna make you come til you’re empty.”

“Shiro-”

“That’s not who I am.”

“Brother, please touch me.” Keith begs.

“There we go.” Shiro wraps his hand around his cock “You’re so wet. I can’t wait to taste you.”

“You-you’d do that? But it’s…”

“It’s what?” Shiro says quietly.

“It’s dirty.” Keith prompts.

“You think it’s dirty? If I’m dirty enough to take advantage of my trusting baby brother, I’m dirty enough to suck dick. I’m even gonna eat you out.”

Keith is barely holding it together, eyes closed and panting.

“W-what does that mean?”

“I’m going to shove my tongue in your ass like it’s your mouth. And I’m gonna suck out- Oh.” Shiro cuts off, looking at the fresh come on his hand.

“It’s okay. Keep going.”

“Are you sure?”

Keith grabs the back of his neck, hauls him down until they’re face to face. “You said you were going to fuck me until I’m empty. You don’t wanna disappoint your little brother, do you?”

 

Later, after Keith has made a mess of them both and Shiro has licked him clean, they lay beside each other on the bed.

“Hey Shiro?”

“Yeah?”

“I love you bro.”

Shiro groans as his dick starts to wake up. “You’re the worst.”

But he lets Keith climb on anyway.


	2. Chapter 2

**Notes for the Chapter:**

> I kinda imply they're high school age for this but uhh... Idk do colleges have football teams? Whatever

Shiro's tired. He hasn't been sleeping, and when he does he dreams of Keith. Of his little brother Keith, with his gorgeous dark hair and his taunting eyes. Shiro buries his face in the pillow. He has to stop, he knows. This isn't right but he can't stop thinking about Keith's body. He sees it often and at times his thinks about quitting the football team to get away from it. He's got a stupidly tiny wasp waist, that Shiro knows fits perfectly in his hands. He's light on his feet as he dodges the other team’s attackers and he's strong enough to throw the ball across the field, accurate enough to hit the goal. 

Keith is incredible. And it makes Shiro groan in despair and arousal.

 

He sleeps. He dreams of keeping Keith behind in the locker room, telling the team he wants to go over the final play. Keith's won the game for them, and Shiro is going to congratulate him.

“Are they gone?”

“Yeah. They've gone to some party.”

“Good.” Keith is already naked. He isn't hard yet but his cock is plump with anticipation. 

“You have something in mind?” Shiro asks causally. He wants to pin Keith against the lockers and fuck him, have Keith hold on to his armoured shoulders and press their faces so close their painted stripes smear across the others cheeks.

Keith raises an eyebrow. 

“I've seen you looking, brother. In the showers, after the game.” There's a bruise on his shoulder. It'd be easy to hide a love bite there. 

“Alright.” Shiro says. “Are you ready?” He's already been helped out of his shoulders, seen Keith's jealous eyes across the room as their teammates got their hands on him. He shoves his vest in the locker, pushes down his sweat darkened boxers.

“What do you think?”

“Baby bro, you were that sure we'd win?”

“Pretty sure. Otherwise it'd have been commiserations.”

“You're cocky.”

“Mmm.”

Keith starts to back towards the showers. He liked to watch him approach, seeing all the muscles that come obediently when he calls. Stepping down into the showers he turns one on, letting the water cascade over him.

“Come on, big bro.”

 

Keith opens the door. It's early and the house is asleep. He shuts the door behind him and creeps forward, stomach churning with nerves and arousal. Keith is glad his brother sleeps like a starfish, and today he even has one knee raised, the foot planted on the mattress. It makes a perfect little tent for him to sneak under. 

Above him Shiro sighs his name in his sleep, and after the terror fades it leaves comfort in the knowledge Shiro is dreaming of him. Keith brushes his lips along muscled thighs, just to feel as he shuffles his way forward. His brother’s cock is thick even when it's soft and the thought of how much bigger it could get makes his brain short out. He mouths at the head through the fabric of his boxers, takes a deep breath. Shiro had been too lazy to shower after the game last night and he stinks. Keith grinds his cock against the sheets. He wants to smell Shiro when he's worked up a sweat fucking him. 

He delicately pulls the prized cock from its confines and presses it against his face, noses it affectionately. Keith takes the head into his mouth, circles his hand around the base to keep it steady as it thickens. It stretches his lips and he feels his cock leak into the sheets, his ass clenching at the thought of taking it. Keith pushes himself further, squeezes his thumb in his fist as he tries to stave off his gag reflex. He should have practiced more but he was desperate to taste his brother and as he tries to take more he chokes loudly and-

“Keith?” The sheet is pulled back to expose him.

Keith flinches, cowering between his thighs. Shiro's never hit him, not even when they were young but surely he will now. He flicks his eyes up.

Shiro is smiling sleepily. He looks happy, and one of his hands pets clumsily at Keith's hair.

“Thought I was awake for a moment there.”

“You sure you're not awake?” Keith says quietly.

“I'm not that lucky. Not lucky enough for you to love me back.” Shiro cups his face, a thumb pulling at his wet lower lip. “I dreamt you let me fuck you in the locker room showers. I always dream that you love me.”

“I do love you.”

“Dream Keith always says that.” His voice is sad. 

“How can I prove I'm real?” Keith asks. He's edged forwards to rest on his brother's lower stomach. 

“Kiss me. I always wake up before we kiss.”

Keith scrambles to oblige but Shiro stops him. 

“Wait a moment. Let me look at you like this. So I can remember.”

“You can look at me as much as you want.”

Shiro snorts. “Nah. I'll wake up and you'll be just my little brother again.”

Keith shakes his hands off and smashes their mouths together. Shiro's eyes widen.

“I'm awake?!”

“I told you.”

“Holy fuck.” Shiro's arms wind around him. “Keith.”

“It's me, Shiro. I love you.”

“Keith.” He says again, awestruck as he pulls Keith close to kiss him. “I love you Keith.”

Shiro rolls them over, settling naturally between his brother's legs. Keith is wearing boxers and an old shirt of Shiro's. It's worn soft and the print is faded, the neckline slipping down his shoulder.

“You're so beautiful.” Shiro sighs. “Your mouth felt good. Don't break my heart and tell me you've been practicing on other guys.”

Keith shakes his head. “I have a dildo. But it's not as big as you.” His cheeks are pink. “I wanted to make you feel good.”

“Baby.” Shiro coos in his ear. “Everything about you makes me feel good.”

He lowers his hips, presses his erection against Keith's clothed dick. 

“Can I get us off like this?” Shiro moves his hips a little to show what he means

Keith nods. Suddenly he folds a leg against his chest, slips his foot out of his underwear, and Shiro gasps. His little cock is hard, pointing up at Shiro like a flower to the sun. Shiro wants to put his mouth on it, to return the favour but Keith's legs hook lazily around his thighs. He can't help but rub their bare cocks together, watches Keith bite his lip. 

“Please brother. I haven't let anyone else touch me.”

“Ever?”

“Ever.” Keith promises. “I wanted it to be you.”

“Please Keith,” Shiro implores, mouthing at his neck. “Don’t let anyone else touch you. Say you’ll be mine.”

“I’ll be yours, I’ll always be yours. I love you.” Keith gasps out as his brother moves against him.

“I love you too, baby brother. I've wanted you for so long. I thought about quitting the team so I wouldn't have to see you undressed.” confesses Shiro.

“Why do you think I joined the team?” Keith groans when he starts to suck on his neck. “You're so goddamned hot.”

Keith's eyes close, head lolling. Shiro cups his face, rests their foreheads together.

“Look at me.”

He opens his eyes, dark with arousal and watery with emotion.

“I want you to see who’s doing this to you. Look at me when I make you come.”

“Shiro, brother…”

“Say it again.”

“Brother.”

“Fuck.” Shiro groans.

Keith comes over his stomach, fingers scrabbling uselessly over his brother’s broad back.

“Keith, you're so perfect. I'm so lucky.” Shiro sighs. He manages a few more thrusts as Keith grits his teeth, before he spills his load as well.

“Whoa…” Keith says, touching the come on his stomach. “You came so much.” His dick twitches.

“Mmm.” Shiro kisses his forehead as he leans over for a tissue.

He finds Keith scooping their mixed come from his skin and sucking his fingers clean.

“Baby bro, com'on. You can't just go and be sexy when I can't get it up again.” He complains.

“I just wanted to taste you. Since I didn't get to finish sucking you off.” Keith jokingly offers him a white smeared finger. “Want some? You taste good.”

Shiro leans in without thinking, closes his lips around his knuckle and cushioning the fingertip on his tongue. 

“Oh.”

“Alright baby. Let's go to sleep huh?”

“But Shiro… You got me hard again.”

**Author's Note:**

> hustled to finish this to try distract me from s7. let me know what you think :D
> 
> y'all can skip this note if u want. keith's puberty misfire is inspired by uh...me. i was six when my brother (18) moved out and i don't remember him living with us, so he was basically a cool guy who came round to hang out and he always made an effort to know what i liked and he made me feel special bc he listened and he was the big positive male influence in my life. my dad was there too but. i mean obviously nothing ever happened but i think it's affected me in terms of the sort of guy i like and my single biggest, most long time kink


End file.
